ESAB RS 400 User manual

RS 400 / RS 400 with ESU
Thyristorised MMA
Welding Power Source
Instruction manual

RS 400 / RS 400 with ESU
THYRISTORISED MMA WELDING POWER SOURCE
Instruction manual
For
Installation, Operation & General maintenance

CONTENTS
Item Page No.
SAFETY 1-2
ASSEMBLING 3
ACCESSORIES LIST 3
RATING 3
CAUTIONS FOR INSTALLATION 3-4
ITEMS FOR INSTALLATION 4
WELDING OPERATIONS 5
WORKING PRINCIPLES OF ESU UNIT 6
(IN MACHINES FITTED WITH ESU)
MAINTENANCE & INSPECTION 6-7
AFTER SALES SERVICE 7
FAULT FINDING 8-9
WIRING DIAGRAM RS 400 (STANDARD) 10
WIRING DIAGRAM RS 400 WITH ESU 11
TEST POINT VOLTAGES IN CONTROL PCB 12
SPARES IDENTIFICATION – RS 400 13 - 16
RECOMMENDED LIST OF SPARES – RS 400 17

SAFETY
Users of ESAB welding equipment have the ultimate responsibility for ensuring that
anyone who works on or near the equipment observes all the relevant safety
precautions. Safety precautions must meet the requirements that apply to this type of
welding equipment. The following recommendations should be observed in addition to
the standard regulations that apply to the workplace.
Trained personnel well acquainted with the operation of the welding equipment must
carry out all the work. Incorrect operation of the equipment may lead to hazardous
situations, which can result in injury to the operator and damage to the equipment.
1. Anyone who uses the welding equipment must be familiar with:
• its operation
• location of emergency stops
• its function
• relevant safety precautions
• welding
2. The operator must ensure that:
• no unauthorized person is stationed within the working area of the equipment
when it is started up.
• no one is unprotected when the arc is struck
3. The workplace must:
• be suitable for the purpose
• be free from drafts
4. Personal safety equipment
• Always wear recommended personal safety equipment, such as safety glasses,
flameproof clothing, and safety gloves.
• Do not wear loose—fitting items, such as scarves, bracelets, rings, etc., which
could become trapped or cause burns.
5. General precautions
• Make sure the return cable is connected securely.
• Only a qualified electrician may carry out work on high voltage equipment.
• Appropriate fire extinguishing equipment must be clearly marked and close at
hand.
• Lubrication and maintenance must not be carried out on the equipment during
operation.
1

Read and understand the instruction manual before installing or operating.
ESAB can provide you with all necessary welding protection and accessories.
WARNING
Arc welding and cutting can be injurious to yourself and others. Take
precautions when welding.
Ask for your employer’s safety practices which should be based on manufacturers’
hazard data.
ELECTRIC SHOCK – Can kill
• Install and earth the welding unit in accordance with applicable
standards.
• Do not touch live electrical parts or electrodes with bare skin, wet
gloves or wet clothing.
• Insulate yourself from earth and the workpiece.
• Ensure your working stance is safe.
FUMES AND GASES – Can be dangerous to health
• Keep your head out of the fumes.
• Use ventilation, extraction at the arc, or both, to take fumes and gases
away from your breathing zone and the general area.
ARC RAYS – Can injure eyes and burn skin.
• Protect your eyes and body. Use the correct welding screen and filter
lens and wear protective clothing.
• Protect bystanders with suitable screens or curtains.
FIRE HAZARD
• Sparks (spatter) can cause fire. Make sure therefore that there are no
inflammable materials nearby.
NOISE – Excessive noise can damage hearing
• Protect your ears. Use earmuffs or other hearing protection.
• Warn bystanders of the risk.
MALFUNCTION – Call for expert assistance in the event of malfunction.
PROTECT YOURSELF AND OTHERS!
CAUTION!
This product is solely intended for arc welding
Do not dispose of electrical equipment together with normal waste!
In accordance with national law, electrical equipment that has
reached the end of its life must be collected separately and returned
to an environmentally compatible recycling facility. As the owner of
the equipment, you should get information on approved collection
systems from the local representative. By applying this Directive you
will improve the environment and human health
2

ASSEMBLLING
The complete installation should consist the following items:
Description Type Quantity
1. Welding Power Source RS 400 Power
Source 1
2. Remote Controller
(Optional) RCU RS-400 1
ACCESSORIES LIST FOR THYRISTORISED WELDING RECTIFIER RS 400
Fuse, element 1A 1 piece
Instruction Manual 1 piece
RATING OF RS 400 THYRISTORISED MMA WELDING POWER SOURCE
CHARACTERISTICS CONSTANT CURRENT TYPE
Input:
SUPPLY VOLTAGE, PHASE & FREQUENCY 415± 10%, 3 Phases, 50 Hz, AC
RATED INPUT CURRENT 27 A
RATED RATING 19.4 KVA
Output:
OUTPUT CURRENT RANGE DC 10-400A (Single Range)
OPEN CIRCUIT VOLTAGE (NOMINAL) 95 V DC
TYPE OF WELDING CURRENT CONTROL STEPLESS
CLASS OF INSULATION ‘H’
COOLING FORCED AIR COOLED
APPROX DIMENSION (LxWxH) IN MM 825 x 695 x 1070
WEIGHT (APPROX) 195 KG.
CAUTIONS FOR INSTALLATION
a) Capacity of Equipment
Input Voltage AC 415 V 10%
Number of Phase &
Frequency 3 phases, 50 Hz
Capacity of Fuse (B Class) 63 Amps
Input Cable More than 10 mm2
Output Cable More than 50 mm2
3

 Provide a Switch Box for every Welding Power Source, and use designated
fuse
 Tolerance of Power Voltage Variation is 10% of rated input voltage.
 100 Amps MCB to be used as alternative to SFU.
a) Installation place
 Install in the place where less moisture and dust exist. Avoid direct sunlight and
rain, and maintain ambient temperature within –10o to +45o C as much as
possible.
 Keep the welding power source at least 20 cm. away from the wall (if any).
 In case of installation of more two units side by side, a distance of more than 20
cm is recommended between the two power sources.
 Use a shield to protect the welding arc in case of excessive air draft.
c) Ventilation
Adequate ventilation is recommended at the place of installation. For
example the following guideline should be followed:
a) In case of the area being more than 300 square meters (per unit), no
ventilation is required, provided the room is not completely airtight.
b) In case of the area being less than 300 square meters and the welding
is continuously performed, adequate ventilation is recommended with
the help of vent fan or exhaust duct.
c) While performing the grounding work, it is recommended that a skilled
electrician does the work.
ITEMS FOR INSTALLATION
No. Item No. Item
1. Remote Control Unit RS 400
(Optional) 8. Welding cable
2. Work Piece 9. Welding cable
3. Switch Box (Input) 10. Input Cable
4. Connector for Remote Control Unit 11. Electrode Holder
5. Negative Terminal 12. Electrode
6. Positive Terminal 13. Terminal Block input
7. Control Cable for RCU RS 400 14. ON OFF Switch
4

WELDING OPERATION
Once the installation of the equipment is completed, connect the work Cable to
the negative output terminal and the cable end of the electrode holder to the
Positive output terminal. These cable connections should be tightened properly
to avoid electrical heating due to loose connections. Put the main Switch box in
‘ON’. Turn on “Power ON/OFF switch” on the rear panel. The green lamp on
the panel of the Power Source will glow and the fan will start rotating. Now the
equipment is ready. Connect an Electrode with the Electrode Holder. The
welding current can be controlled by the current control potentiometer mounted
on the front panel of the Power source or through Remote Controller as
explained below.
Welding Current Adjustment
Put the “Local / Remote” switch to ‘Local’ mode. Now set the DC output current
as required with the help of the current control potentiometer and ignite an
experimental Arc. For the fine-tuning of the required current, set the parameters
using the Ammeter mounted on the front panel of the power source.
Load Voltage / Open Circuit Voltage
Operate the “Amps/Volts” switch to Volts position; the meter on the front panel
will now indicate the output DC voltage. On releasing this switch, it will
automatically come back to Amps position and the meter will read the output
DC welding current.
Remote Controller
The output Welding current can be increased and decreased as desired from
the operation point with the help of the Remote Controller unit as per the
following guideline, even on load condition.
Set the Local/Remote switch to remote position and connect the remote
controller to the socket provided in the power source. Now set the Welding
current by turning current control potentiometer. Graduation of the current value
mentioned on the Remote Controller Unit should be followed as guideline.
However, for accurate output current, adjust the potentiometer to a proper
value from the METER, mounted on the Front panel of the power source after
generating an experimental arc.
Welding with Cellulosic Electrode
 Put Normal/Cellulosic Switch to Cellulosic Position depending on the
size of the electrode.
 Keep the main potentiometer around the middle position of the scale &
do the welding.
5

Working Principle of Energy Saving Unit:
Energy Saving Circuit is an optional feature in the RS 400 Machine. Working
principle of the ESU is explained below:
The extra items fitted in RS 400 having the Energy Saving feature comprises of:
a) Control Transformer for ESU
b) Control PCB for ESU
c) Line Contactor- ESU
The unit, when energized provides an auxiliary low 55-60 VD.C to the output of the
main Welding Rectifier.
On attempting to strike the welding arc, the output is sensed by the PCB, which
triggers on the coil of the main line contactor. The contactor (3 pole) provides the 3-
phase A.C supply to the welding machine.
The machine is enabled, and welding can be done as usual. The contactor stays ON
throughout the welding period by current sensing circuit (provided by Hall Sensor in
the Machine)
When the welding is stopped, the output of the rectifier reaches the O.C.V of the
machine (about 100 V D.C). The PCB senses this and the disables the main contactor
to switch off the supply to the Machine, and once again the low voltage of 55-60 V DC
appears across the welding terminals, which is a low safe voltage.
In the no-weld condition, the line contactor remains disabled, and the Main
Transformer also remains unconnected, thereby reducing the no-load losses of the
machine to a very low value
MAINTENANCE & INSPECTION
The maintenance and inspection should be carried out only after the switches
in the Main switch box certainly turned OFF.
Try to maintain and inspect the set regularly as per the following guide lines.
a) Regular Inspection
Every 3-6 months, depending on operation frequency:
Inspection Portion Inspection Point Maintenance Method
Fuse Box Fastening & Looseness
at the Connection.
Confirmation of proper
fuse
Refer to the Equipment
capacity
Input and Output
Connections Fastening & Looseness at the Connection.
Confirmation of
Installation
Faster first and Tape
Interior of Welding
Power Source Sedimentation of Dust. Trace of Overheat. Blow off dust with Compressed Air.
6

b) Cautions to Insulation Voltage – Proof Test & Insulation Resistance
Measurement Test:
Careless execution of Dielectric Strength test and Insulation Resistance
Measurement will cause damage to the power source since thyristors,
transistors and other semiconductor parts are used in the unit. While
conducting these tests in accordance with the by-laws of your company, the
following steps should be performed first: -
 Take of the cables from the switch box that are connected to the three
input terminals and short circuit the three input terminals.
 Take off the cable that is connected to two output terminals and short
circuit the two output terminals.
 Short circuit between positive and negative output of Rectifier bank with
three AC terminals of rectifier bank.
 Use 500 V Megger only.
 Go back to original conditions removing short-circuit etc. once the test is
over.
AFTER SALES SERVICE
In case of any abnormality observed during usage of the equipment,
which could not be rectified at site, please contact immediately Area
Sales Manager of the nearest unit of ESAB INDIA LIMITED with the
following details:
1) Serial Number of the equipment & type
2) Nature of the complaint with the relevant details, if possible and the
details of Input Supply.
3) Date of purchase of the equipment and the date of commissioning.
The qualified and trained service teams of ESAB INDIA LIMITED,
located of the zonal head quarters render the after sales service to the
customers and also assist in intelligent selections of Welding Equipment
& consumable for various applications.
7

FAULT FINDING
Abnormality Possible Cause Corrective action
Wait and keep the power switch
‘ON’ to keep the fan running at
no load. The Warning Lamp
should get off within 10-15
minutes. Only after that has
happened. adjust Welding
Current and / or duty cycle to
lower levels and restart welding
Welding automatically
stops and the WARN
LAMP glows
The equipment is over loaded
Avoid welding operation if the
indicator ‘WARN’ gets
repeatedly on
The current adjustment
does not work in Remote
mode only
Loose Connection in the
Remote plug & socket or any
interconnection wire
disconnected or Remote
Pendant Potentiometer faulty
Fasten the plug & Socket firmly,
check for wire discontinuity and
rectify, check Remote unit
potentiometer and replace if
necessary
Faulty potentiometer of
current control on the front
panel of the power source
Check with a multimeter replace,
if found defective.
Remote/Local switch not in
proper position Check the position of the Remote/Local switch and
position properly.
Fault in PCB Replace PCB
One phase is missing. Check and rectify input supply
voltage.
The current adjustment
does not work
Rectifier bank damaged Replace Rectifier bank
Fault in AC Supply Check 3 ph input AC supply
voltage
Fan does not rotate
when Power Switch is
On Fault in control transformer Check 0-200 V winding
Fault in AC input Check 3 ph input AC
OCV less than 60V when
Power Switch is On Fault in PCB Replace PCB
Fault in PCB Replace PCB
Fault in potentiometer on
front panel Check & Replace
Welding Current can not
be controlled
Shunt connection to PCB
disconnected Check and rectify
Supply voltage fluctuations (
greater than ± 10%) Check and rectify
Wrong polarity used for the
electrode Check and rectify
Damaged main Rectifier bank Replace the rectifier bank
Unstable arc
One phase missing Check and rectify
8

ADDITIONAL FAULT FINDING FOR MACHINES WITH ESU
Abnormality Possible Cause Corrective action
Arc striking can not be
done Faulty Line Contactor Check and replace
Faulty ESU PCB Check and replace
Faulty ESU Control
Transformer Check and replace
Line Contactor does not
get off after a certain
delay after welding is
stopped
Faulty ESU PCB Check and replace
Line Contactor always
remains ON (OCV does
not reduce to 55-60 V
level within 50-
60 seconds
after welding has been
stopped)
Faulty ESU PCB Check and replace
Welding can be started,
but erratic current control,
arc drops down
Faulty ESU PCB Check and replace
Hall Sensor faulty Check and replace
9

WIRING DIAGRAM- RS 400 (Standard)
10

WIRING DIAGRAM- RS 400 (with ESU)
11

TEST POINT VOLTAGES IN RS 400 CONTROL PCB
All voltages except Gate- Cathode measurements are to be measured with
respect to TP1 (0V point on Control PCB)
TEST POINT VALUE
TP2 +15 V ± 0.2 V DC
TP3 -15 V ± 0.2 VDC
TP5
+12 V ± 0.2 VDC (Current control potentiometer at
max. setting)
TP5 +6 V ± 0.2 VDC (Current control Potentiometer at
200 A setting.)
TP10 +9.5 VDC (Current control Potentiometer at
minimum setting)
TP10 + 10.44 VDC (Current control Potentiometer at
maximum setting)
TP11 8.4 V ± 0.05 VDC (Current control Potentiometer
at maximum setting)
TP12 0 – 18 V AC
TP17
TP22
TP13 7.5 VDC
TP18
TP23
TP14 7.5 VDC
TP19
TP24
Gate- Cathode voltages measured at connector CN2
Ferrule numbers 9-10 0.039 V ± 0.01 V at no load
Ferrule numbers12-13
Ferrule numbers15-16
12

SPARES IDENTIFICATION OF RS 400
RS 400 SIDE VIEW
13
17
15
10
12
21
26

RS 400 TOP VIEW
14
11 17
27
2
6
7
9

RS 400 FRONT VIEW
15
5
24 3
20
19
4
22
16
13
23
18

RS 400 REAR VIEW
16
1
25

RECOMMENDED LIST FOR SPARE SPARTS
Recommended HoldingSL. NO.
ITEM CODE DESCRIPTION 1-10 Above 10
1 1611621199 On-Off Rotary Switch 1 2
2 1611621300 Synchronizing PCB 1 2
3 1611642019 Fuse Element 1 A 2 4
4 1611642020 Amp/ Volt Selector Switch 1 2
5 1611642021 Dual Scale Ammeter + Voltmeter 1 2
6 1611642023 Filter Capacitor 8 µF 1 2
7 1611642024 Bleeder Resistor 10 Ω /10W 1 2
8 1611642026 Power Resistor 50 Ω / 200W 2 4
9 1611642050 Bleeder Resistor 10KΩ / 20W 1 2
10 1611642403 Main Transformer - 1
11 1611642404 Control Transformer 1 2
12 1611642420 DC Choke - 1
13 1611642430 Control PCB 1 2
14 1611642431 Snubber PCB Assy. (with Harness) 1 2
15 1611642441 Rectifier Bridge (SCR) - 1
16 1641675046 Electrode Type selector switch 1 2
17 1651684041 Cooling Fan 1 2
18 1651685035 3 Pin Connector for Remote Unit 1 2
19 1651685051 LED Light (Green) 1 2
20 1651685052 LED Light (Red) 1 2
21 1651685078 Shunt 400 Amps 1 1
22 1651685117 Local / Remote Selector Switch 1 2
23 1651685125 Output Terminal 1 2
24 1651685206 Potentiometer 5 KΩ 1 2
25 1651685236 Input Terminal Block Assy. 1 2
26 4651685033 Output ZNR Assy. 1 2
27 4651685040 Input ZNR Assy. 1 2
SPARE LIST FOR ADDITIONAL ITEMS IN MACHINES FITTED WITH ESU
Recommended HoldingITEM CODE
DESCRIPTION 1-10 Above 10
1611642302 ESU PCB 1 2
1611642651 Control Transformer-ESU 1 2
1651684056 Line Contactor 1 2
1651683020 HALL Sensor 1 2
17